After the upgrade from lion iCalendar doubles birthdays.
Now I have an announcement for the same birthday one two days.
On the second day the person is now one year older iCal says :-)
Refer to this article.
iCloud: Resolving duplicate calendars after setting up your calendar application for iCloud Calendar
Thanks, but this article does not solve the problem.
I think somthing is wrong with the notification centre, because only birthdays which are displayed in the NC are doubled...
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